Multi-homed computers provide access to network resources over parallel paths. A multi-homed computer can have multiple network interfaces to connect the computer to two or more networks. For computers using Transmission Control Protocol/Internet Protocol (TCP/IP), these interfaces can be separate network interface cards (NICs) and/or multiple IP addresses on one NIC.
In order to route network traffic to its destination, conventionally, routing decisions are based upon system wide policy(ies). The policy(ies) can be implemented through a table of routes that describe the network over which a particular destination IP addresses can be reached. The table of routes is typically maintained at a system level.
Virtual private networks (VPNs) facilitate secure communication between endpoints (e.g., a user computer and a VPN server computer). Often, in a multi-homed environment, communications that need to be secured may not be routed through the VPN channel. For example, a user may desire to communicate via a VPN while communicating in an unsecure manner over the Internet.